Ribbon spool

ABSTRACT

A ribbon spool for typewriter ribbon includes a pair of molded plastic spool components each having a circular flange from which a pair of spaced, cylindrical, coaxial internal and external telescoping hubs project. An axial hole in the smallest diameter hub is aligned with central holes in each of the flanges to permit the overall spool to accept the upstanding spindle of a business machine. A ribbon retaining element in the form of a sheet metal clip is adapted for insertion on the smallest diameter hub prior to joining of the two spool components. The clip is then held captive on the spool by the hub with which the smallest diameter hub mates and by a slot in the flange of the other spool component which accepts a tab on the metal clip. A prong on the clip is adapted to engage the typewriter ribbon. As an alternative securing means, a pair of aligned slots in the external mating hubs, accessible via a cutout in one of the flanges with the spool in the joined condition, accept and retain the end of a typewriter ribbon of the type having an edgewiseoriented bar clamped thereto.

Q United States Patent 1 3,679,039 Landgraf 51 July 25, 1972 [s41 RIBBON SPOOL 3,497,050 2/1970 Landgraf ..197/175 [72] Inventor: Walter D. Landgraf, 9628 S. Kildare Ave., FOREIGN PATENTS OR APPLICA'HONS Oak Lawn, [11. 60453 336,674 5/1921 Germany ..l97/l75 1 Filed: J y 25, 1969 736,505 6/1943 Germany ..197/175 [21] Appl No 844,993 Primary Examiner-Ernest T. Wright,.lr.

Attorney-Hurvitz, Rose & Greene [52] U.S. Cl ..l97/l75 [51 Int. Cl. ...B41j 35/00 [57] ABSTRACT [58] Field of Search l 97/ l 75 A ribbon Spool for typewriter ribbon includes a p of molded [56] References Cited plastic spool components each having a circular flange from WlllCll a pair of spaced. cylindrical, coaxial internal and exter- UNITED STATES PATENTS nal telescoping hubs project. An axial hole in the smallest diameter hub is aligned with central holes in each of the 928,001 7/1909 0 Connor ..l97/l75 flanges to permit the overall Spool to accept the upstanding 2,873,839 2"959 Bfshop 97/175 spindle of a business machine. A ribbon retaining element in 3,042,180 7/1962 Bishop 197/175 the form of a sheet metal clip is adapted for insertion on the 3,093,231 696?, Lfmdgrafw smallest diameter hub prior to joining of the two spool com- 1 1,273 10N965 BlshOP 197/l75 X ponents. The clip is then held captive on the spool by the hub Rl 1,097 7/1390 y "197/175 with which the smallest diameter hub mates and by a slot in 2,232,461 2/1941 Kuckhoff -197/175 X the flange of the other spool component which accepts a tab 2,366,147 12/1944 y -197/175 UX on the metal clip. A prong on the clip is adapted to engage the 2,667,257 1/1954 "unado 75 typewriter ribbon. As an alternative securing means, a pair of 2,925,164 2/1960 M p y 197/175 aligned slots in the external mating hubs, accessible via a cu- 2. 3/1960 l f 197/175 tout in one of the flanges with the spool in the joined condi- 3,065,838 I 1/l962 Biedinger et a1 ..l97/l75 on, accept and retain the end f a typewriter ribbon f the 3,120,177 2/1964 Clark I 97/1 75 X type having an edgewiSe ol-iemed bar clamped thereto 3,323,743 6/1967 Landgraf. 197/175 UX 3,393,790 7/1968 Dixon 197/1 75 7 Claims, 5 Drawing Figures Patented July 25,1972 AVAILABLE C P-l 3,679,039

INVENTUR' WRLTER D. LRNDGRQF BBZMZHZM ATTORNEYS RIBBON SPOOL BACKGROUND OF THE INVENTION The present invention relates generally to spools for typewriter ribbons, and in particular to a typewriter ribbon spool of molded plastic construction having associated therewith a metal clip to retain a ribbon in securely fastened relationship to the spool.

While typewriter ribbon spools of molded plastic construction have become quite popular in recent years, one problem with such spools resides in the provision of suitable means by which to clamp or retain a ribbon on the spool with easy access for convenient changing of the ribbon by secretarial personnel. Some typewriter ribbons are provided at one end with a metal eyelet, or with a thin metal strip clamped edgewise at the very end of the ribbon, or in some cases the ribbon end has merely a slit therein, to permit ribbon attachment to the spool. For molded plastic ribbon spools of two-piece construction, it has been the practice in many instances in the prior art to clamp the ribbon between the spool components because the spool is not readily provided with a catch or projection by which to otherwise retain the ribbon thereon.

It is a principal object of the present invention to provide a molded plastic ribbon spool with new and improved ribbon securing means.

It is a further object of the present invention to provide a molded plastic typewriter ribbon spool of two-piece construction having ancillary means for securing a ribbon thereto.

SUMMARY OF THE INVENTION Briefly, according to a preferred embodiment of the present invention, a pair of spool components of molded plastic construction each comprises a substantially circular flange member having a pair of spaced tubular hubs projecting therefrom in coaxial relationship, the hubs on one of the members being constructed and arranged to telescope into and nest snugly within the hubs on the other member. The external hub of each component is provided with a rather wide slot and the spool components are constructed and arranged to telescope together in only one specific position of alignment such that the two relatively wide slots in the external hub are radially aligned.

A metal clip, having a prong for entry into a slit or eyelet constituting the securing means on the end of the inked ribbon, is provided with an integral retaining ring to slip over the smallest hub of the two spool components and to be held captive when the smallest hub is mated (telescoped) with the associated or cooperating hub on the other spool component. The metal clip is also provided, at the end opposite the retaining ring, with a projecting tab that enters a small slot in the flange of the spool component, further serving to maintain the clip in fixed, captive relation with the two spools components when those components are joined together to form a double flange typewriter spool.

A portion of each external hub of the two spool components is sliced away at the aforementioned radially aligned slots to space the metal clip from the outer surface of the most external hub, at a point of tangency to the circle described by the circumference of that hub, when the two components are joined together. Such an arrangement allows easy attachment of the ribbon to the spool by insertion of the prong on the clip into the slit or eyelet or other entry means in the ribbon end, and then wrapping of the ribbon about the external hub surface and the clip itself.

A further pair of radially aligned slots are provided in the external hub of each of the spool components at a point diametrically opposite the first-mentioned pair of slots. The slot in the most external hub member, of the further pair of slots, is made very narrow to permit retention or capture of a metal bar clamped to the end of a typewriter ribbon of another commercially available type. A gap or cutout in the flange of one of the spool components extends over the two external hubs exposing the last-mentioned radially aligned slots therein, to permit insertion of the metal bar at the end of the ribbon into the aligned slots for retention therein with the spool in the joined condition.

BRIEF DESCRIPTION OF THE DRAWING FIG. I is an exploded perspective view of an embodiment of a ribbon spool in accordance with the present invention, illustrating the manner in which the spool components telescope together;

FIG. 2 is a perspective view of the double flange ribbon spool formed by the spool components of FIG. 1, with a portion of the lower flange (relative to the usual orientation of the spool in a business machine) broken away to show the ribbonsecuring metal clip;

FIG. 3 is a section view taken along the lines 3--3 of FIG. 2;

FIG. 4 is a section view taken along the lines 44 of FIG. 3; and

FIG. 5 is a view of the metal clip in its flat planar form prior to bending or deformation to produce the clip structure shown as the central component in FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawing, a complete ribbon spool 10 (FIG. 2) includes a pair of molded plastic spool components ll, 12 (FIG. 1), each having a circular flange 13, 14, respectively, and a pair of spaced coaxial tubular hubs 15, 16, and 17, 18 projecting in axial relation from the respective flanges 13 and 14. The internal hub 16 of spool component 11 has the smallest diameter of the four hubs 15, 16, 17, 18 and is provided with an axial hole 20 that is aligned with central holes 21, 22 in each of the flanges 13, 14, respectively, when the hubs 15, 16, 17, 18 are joined together to form a complete ribbon spool 10. This allows placement of the spool 10 on the driving spindle (not shown) of the business machine, such as a typewriter, (not shown) in which the spool 10 is to be utilized.

The hubs l5, 16 of spool component 11 are constructed, arranged, and dimensioned (as are the hubs l7, 18 of spool component 12) to telescope into hubs 17, 18, respectively, of spool component 12, in snug nesting relation. The external hub 15 of spool component 11 is provided with a longitudinally extending slot 25 (FIG. 1) that is constructed, arranged and dimensioned to accept a projection 26 (FIG. 1) on the interior surface of the cooperating external hub 17 of the other spool component 12, to permit the hubs l5, 16, 17, 18 to telescope completely together in only one position of radial alignment. Each of the external hubs 15 and 17 is also provided with a pair of slots 28, 29 and 30, 31, respectively, (FIG. 1) extending longitudinally the entire lengths of the respective hubs 15 and 17 at diametrically opposite positions thereon, for purposes which will be explained presently.

As shown in the Figures, the external surface of hub 15 is splined to mate with splines on the internal surface of hub 17 to provide some added friction against relative rotation of the two hubs l5 and 17 when joined together. However, the use of splines is not absolutely necessary since the two components 11, 12 are locked effectively against rotation by engagement of projection 26 in slot 25.

When the spool components l1, 12 are properly aligned in radial orientation, they can telescope together with complete nesting relation of their respective hubs 15 and 17, projection 26 entering the small slot 25. The respective longitudinal slots 28, 30 and 29, 31 in the external hubs l5 and 17 are then radially aligned such that the complete double flanged ribbon spool 10 is provided with a wide slot (formed by slots 28, 30) in its mating external hubs l5, l7, and a relatively narrow slot (formed by slots 29, 31) at a location in the mating external hubs 15 and 17 diametrically opposite the wider slot. This is most readily seen in FIG. 4. The complete cylindrical configuration of the hubs l5 and 17 is disrupted by a slice taken along a plane through a chord normal to the radial line through a point which is to be the center of the wider slot.

A metal clip 35 having a prong 36 projecting substantially centrally thereof (FIGS. 1, 2, and is provided with a conjoined or integral perpendicularly extending retaining ring 37 at one of its ends and a small tab 38 at the other end. The retaining ring 37 is provided with a central hole 40 to permit it to be slipped over the smaller diameter hub 16 of spool component 11. When the two spool components 11, 12 are telescoped together, ring 37 is sandwiched between the rim of hub 18 and the immediately opposite surface of flange 13, and is thereby held captive. Also, when the two spool components 1 l, 12 are radially aligned and completely telescoped together in locked relation by the entry of projection 26 into the slot 25, the tab 38 of the sheet metal clip 35 is aligned with and enters a small slot 42 (FIG. 1) in the flange 14 of spool component 12. This serves to lock clip 35 in fixed relation to mated external hubs 15, 17 in the overall double flange spool 10.

Formation of metal clip 35 with its retaining ring 37 is best illustrated in FIG. 5, where the overall clip 35 is shown as it may be stamped from a relatively thin piece of rigid sheet metal (e.g., steel). The metal retaining ring portion 37 is then bent at a angle of 90 to the remainder of metal clip 35 at the bend line 45. The distance between the bend line 45 and the point at which tab 38 joins the body of the clip 35 should be substantially equal to the separation of the flanges 13, 14 with the spool in the completely joined condition.

When the two spool components ll, 12 are telescoped together in complete locked relation with metal clip 35 locked or clamped therebetween, the overall spool 10 is ready to accept and to retain a typewriter ribbon 50 about the periphery of the mating hubs 15, 17. To that end, the prong 36 is hooked or inserted into the slit 48 (FIG, 1) or other opening in one end ofa typewriter ribbon 50, and the ribbon 50 is then wound on the spool 10. As may be observed most clearly in FIG. 4, the axial portion of the body of clip 35 is substantially tangent to the extension of the circumference of the mated hubs 15, 17 (as shown dotted in FIG. 4). Thus, the ribbon 50 may be wound on the spool 10 in substantially circular layers.

The wide opening provided by slots 28, 30 provides a space between metal clip 35 and the outer surface of external hub 17, to permit easy insertion of prong 36 into the opening 48 in the ribbon end.

The other set of aligned slots 29, 31 at the diametrically opposite point of the telescoped external hubs 15, 17 provides an alternative arrangement for securing a typewriter ribbon 55 to double flange spool 10. In this respect, it will be observed that slot 29in the inner hub of the external telescoping hubs 15, 17 is substantially wider than slot 31 in external hub 17, and that slot 31 is provided with angular cuts at its sides to run from a wider slot opening to a relatively narrower slot opening at the exterior surface of hub 17. A gap or cutout 52 (FIG. 4) is provided in the circular flange 13 of spool component 11, extending beyond the telescoped external hubs 15, 17 of the overall spool 10 so that access is permitted to the radially aligned mating slots 29, 31 with the two spool components 11, 12 joined together. Such an arrangement permits a ribbon 55 of the type having a metal bar 54 clamped edgewise at one of its ends (FIG. 2) to be inserted into the aligned slots 29, 31 and to be held captive therein since the slot 31 in most external hub 17 is sufficiently narrow, at least at the exterior surface of that hub 17, to prevent the ribbon bar 54 from being pulled therethrough. The ribbon 50 may thereafter be wound about the external surface of the telescoped hubs 15, 17 of the spool 10.

A lever 57 is provided to slide into slots in circular projections 58, 59 on the upper surface of spool component 11 as it is oriented in the business machine, in a manner described in my previous US. Pat. No. 3,323,743, to lock the double flange spool 10 to the driving spindle of the machine. F urthermore, a set of equiangularly-spaced holes 60 are provided on the underside of the flange 14 of spool component 12 to accept, at any of a plurality of spaced points, the spool drivereverse pin (not shown) of the ribbon driving-reverse mechanism of the business machine in which the spool 10 is used.

lclaim:

l. A ribbon spool for use with an inked ribbon having a securing means at one end thereof, said spool comprising a pair of spool components of molded plastic construction. each of said components including a substantially circular flange and a pair of spaced coaxial tubular internal and external hubs projecting axially from said flange, said internal and external hubs on one of said spool components being constructed and arranged to telescope into snug nesting relation with the respective internal and external hubs on the other spool component to form a double flange ribbon spool, and metal clip means including a sheet steel annulus restrained between two adjacent hubs of said components and further including an integral element extending parallel to the axis of said hubs but located externally thereof and captivated between said flanges, said clip means including a hook for engaging said securing means.

2, The spool according to claim 1 wherein telescoped external ones of said hubs have radially aligned slots which are radially aligned with said element extending parallel to the axis of said hubs, said metal clip means being positioned at a point of tangency to the circle defined by the outer circumference of the outermost of said hubs such that said ribbon may be wound about the telescoped hubs and said metal clip means in substantially circular layers after engagement by said hook.

3. The spool according to claim 2 wherein said hook is oriented generally parallel to each said flange of said double flange spool, said annulus having an internal diameter selected to snugly accept the smallest of said hubs and is oriented generally parallel to each flange of said double flange spool, said annulus being clamped between the rim of the hub into which said smallest hub telescopes and the immediately ad jacent flange from which said smallest hub projects when said spool components are joined together with said hubs in snug nesting relation, and said element including an end tab, one of said flanges having a slot located so as to accept said tab.

4. The spool according to claim 1 wherein is further provided an axially extending slot in each of said external hubs, means for restricting said spool components to a single position of relative radial orientation for telescoping of said hubs into complete nesting relation, said single position of relative radial orientation being that for which said axially extending slots are radially aligned, said radially aligned slots having an opening sufficient to accept a single thickness of said ribbon but to retain any further thickness of material which may be clamped to said ribbon, whereby to provide an alternative means for retaining ribbon on said spool.

5. The spool according to claim 4, wherein is further provided a cutout in one of said flanges extending from the edge thereof radially to a point inwardly of the radially aligned slots.

6. A ribbon spool, comprising a first component including a first flange and first and second coaxial hollow hubs of different diameters extending perpendicularly of said first flange and secured to said first flange, a second component including a second flange and third and fourth coaxial hollow hubs of different diameters extending perpendicularly of said second flange, said first hub being smaller than said third hub and snugly telescopic within said third hub, said second hub being smaller than said fourth hub and snugly telescopic within said fourth hub, interacting means which are elements of said second and fourth hubs, respectively, for enabling complete telescoping of said hubs in only one relative angular orientation of said hubs with respect to one another about said axis, said hubs being all coaxial, a ribbon securing element comprising a sheet metal annulus fitting about said first hub and held flat between said third hub and said first flange, said ribbon securing element further including an integral sheet metal extension of said annulus, said extension extending parallel to the axis of said hubs but externally of said hubs, and means securing the free end of said extension to said second flange.

7. The combination according to claim 6, wherein is further provided narrow longitudinal slots extending parallel to the axis of the two largest of said hubs between said flanges, said longitudinal slots being aligned when said spool is assembled, and a radial opening in one of said flanges extending from an 5 edge of said one of said flanges to at least said slots. 

1. A ribbon spool for use with an inked ribbon having a securing means at one end thereof, said spool comprising a pair of spool components of molded plastic construction, each of said components including a substantially circular flange and a pair of spaced coaxial tubular internal and external hubs projecting axially from said flange, said internal and external hubs on one of said spool components being constructed and arranged to telescope into snug nesting relation with the respective internal and external hubs on the other spool component to form a double flange ribbon spool, and metal clip means including a sheet steel annulus restrained between two adjacent hubs of said components and further including an integral element extending parallel to the axis of said hubs but located externally thereof and captivated between said flanges, said clip means including a hook for engaging said securing means.
 2. The spool according to claim 1 wherein telescoped external ones of said hubs have radially aligned slots which are radially aligned with said element extending parallel to the axis of said hubs, said metal clip means being positioned at a point of tangency to the circle defined by the outer circumference of the outermost of said hubs such that said ribbon may be wound about the telescoped hubs and said metal clip means in substantially circular layers after engagement by said hook.
 3. The spool according to claim 2 wherein said hook is oriented generally parallel to each said flange of said double flange spool, said annulus having an inTernal diameter selected to snugly accept the smallest of said hubs and is oriented generally parallel to each flange of said double flange spool, said annulus being clamped between the rim of the hub into which said smallest hub telescopes and the immediately adjacent flange from which said smallest hub projects when said spool components are joined together with said hubs in snug nesting relation, and said element including an end tab, one of said flanges having a slot located so as to accept said tab.
 4. The spool according to claim 1 wherein is further provided an axially extending slot in each of said external hubs, means for restricting said spool components to a single position of relative radial orientation for telescoping of said hubs into complete nesting relation, said single position of relative radial orientation being that for which said axially extending slots are radially aligned, said radially aligned slots having an opening sufficient to accept a single thickness of said ribbon but to retain any further thickness of material which may be clamped to said ribbon, whereby to provide an alternative means for retaining ribbon on said spool.
 5. The spool according to claim 4, wherein is further provided a cutout in one of said flanges extending from the edge thereof radially to a point inwardly of the radially aligned slots.
 6. A ribbon spool, comprising a first component including a first flange and first and second coaxial hollow hubs of different diameters extending perpendicularly of said first flange and secured to said first flange, a second component including a second flange and third and fourth coaxial hollow hubs of different diameters extending perpendicularly of said second flange, said first hub being smaller than said third hub and snugly telescopic within said third hub, said second hub being smaller than said fourth hub and snugly telescopic within said fourth hub, interacting means which are elements of said second and fourth hubs, respectively, for enabling complete telescoping of said hubs in only one relative angular orientation of said hubs with respect to one another about said axis, said hubs being all coaxial, a ribbon securing element comprising a sheet metal annulus fitting about said first hub and held flat between said third hub and said first flange, said ribbon securing element further including an integral sheet metal extension of said annulus, said extension extending parallel to the axis of said hubs but externally of said hubs, and means securing the free end of said extension to said second flange.
 7. The combination according to claim 6, wherein is further provided narrow longitudinal slots extending parallel to the axis of the two largest of said hubs between said flanges, said longitudinal slots being aligned when said spool is assembled, and a radial opening in one of said flanges extending from an edge of said one of said flanges to at least said slots. 